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Custom IC Design Forums

CDF Parameter Passing to the Netlist

I would like to create the hspiceD (or spectre, doesn't really matter) netlist for a circuit, let us call it depth0. This circuit has a subblock, i0, which is an instance of cell depth1. Inside depth1, there is a resistor and a capacitor. In addition, depth1 has a parameter called myParam (defaults to 1) that I would like to pass to the netlist. In other words, I would like to create a netlist like this:

To achieve this, I have edited the CDF parameters of depth1 (Scope:Cell, Layer:Base). I added a parameter called myParam, type:String, Default Value:1, Parse as CEL:yes, Parse as Number:yes, Store Default:yes. When I build the dept0 schematic and add the depth1 symbol, I can see the myParam parameter in the symbol view. In the Simulation Information of the CDF parameters window, in hspiceD simulator, I added myParam in instParameters section.

When I netlist, I do get the netlist above without the myParam value. In other words, the bold line above in the actual netlist is this:

xi0 in0 out0 depth1

If in the stop view list, I put schematic, then I do get the bold line as I want, (i.e. xi0 in0 out0 depth1 myParam=1), but then the netlister does not descend into i0, and the netlist file does not include the depth1 subckt at all.

Is there a way to keep both the parameter value and the subckt information in the netlist?

I am having the same issue with spectre. If I use the parameter inside the lower level schematic, parameter shows up in the netlist. However, I want this netlist to include the defined parameter even if I don't use itin the lower level schematic. Is there a workaround? Is there a dummy block I can add to include these in the netlist?

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